E.g.f.: exp( Sum_{n>=1} n!^2*x^(2*n)/(2*n)! ) = Sum_{n>=0} a(n)*x^(2*n)/(2*n)!.

A193441

E.g.f.: exp( Sum_{n>=1} n!^2*x^(2*n)/(2*n)! ) = Sum_{n>=0} a(n)*x^(2*n)/(2*n)!.

Terms

    a(0) =1a(1) =1a(2) =7a(3) =111a(4) =3089a(5) =131985a(6) =7977687a(7) =645443295a(8) =67165412385

External references